Hi, I have a struct like this: struct KeyboardState { uchar keys[256]; } then I want to update the keyboard state like this: KeyboardState* keyboard = new KeyboardState(); hr = di_keyboard->GetDeviceState(sizeof(keyboard->keys), (LPVOID)keyboard->keys); (LPVOID)keyboard->keys is the thing that doesn't work, how do I do it correctly? There's a reason that I put the keys buffer in it's own struct, I tried it with a simple uchar keys[256] as in the documentation just to make sure and it works with that. So I hope you can help me :)

Yes, the keyboard ptr is valid, I still receive a segmentation fault with the parentheses around keyboard->keys however the program won't crash immediately now.